Tapping machine



M. H. EMRICK TAPPING MACHINE Dec. 18, 1951 mmymm Filed June 5. 1948 INVENTOR MELVIN H. EMRICK ATTORNEY to the workpiece.

Patented ec. 1 8, `1951 UNITED STATES PATENT OFFICE 2,578,995 TAPPINGMMACHINE Melvin H. Emrick, Jamaica, N.`Y. Application Janes, 194s, seria.; Nq. 31,253 4 claims. (C1. 10-129) This invention relates to machines for operating tapping attachments to move the tap of the attachment toward and from the work. More particularly, the invention deals in a novel mounting of the tap supporting head in the machine so that the drive to said head is maintained stationary while the head moves axially with `respect to the drive. `The novel features of the invention will be best 'understood from thefollowing `description when taken together with the accompanying drawing, in which certain embodiments of the invention Vare disclosed, and in which the separate parts are designated by suitable reference characters -in each of the views; and in which:

Fig. 1 is a side View of a machine made according to my invention, with parts of the construction broken away.

Fig. 2 is an enlarged sectional view through the head end of the machine, and omitting the tap attachment.

j Fig.` 3 is a section on the line 3 3 of Fig. 2, showing parts of the construction in elevation and sho-,wing a slight modification; and

Fig. `l is an enlarged `broken sectional view similar to Fig. 2, but showing only parts of the construction.

This invention relates to machines of the general type and kind disclosed in Patent Number 2,079,371, dated May 4, 1937, and deals `more particularly with the structure of the upper or `head end of the machine, and still more particularly, with the mounting and operation of the tapping attachment supporting plate-or adaptor. Further, with the provision of means for taking up the torque to which the attachment is subjected.

In the drawing, I have shown at the base of the machine, in which is pivoted a foot pedal Il for raising and lowering the tapping attachment or the tool supported therein with respect Pivoted to the pedal is a rod |2 which extends to the operating mechanism, the arm of which is shown at I3, in other words, movement imparted to the rod |2 by pedal is transmitted to `arm I3. At |4 is shown a series of weights for counterbalancing the attachment to normally support the attachment in raisedA` position. At I5 is shown an adjustable stop bolt limiting downward movement of the attachment. Extending upwardly from the base is a tubular column I6 through which the rod |2 passes, and supported at the upper end of the column is a head I1 supporting a suitable hood or housing I8, a drive motor i9 and a casing 20 in which the mechanism is arranged for support and guide of a tapping attachment 2|.

On the motor shaft are a series of pulleys 22 `over which is passed a belt, indicated at 23 in Fig. 2 of the drawing, which passes around another series of pulleys 24 secured to the upper end of a 'tube25: The tube 25 is mounted for free rota- .tion in upper and lower ball bearings 26 andZ'liil arranged in the casing 20. 'I'he tube 25 has two shoulders 28 and 25 on which are seated rings 3U and 3| to provide wide bearing supporting surfaces for the inner races of the bearings 26 and 2l. A washer 32 is disposed upon the upper surface of the bearing 26` and a nut 33 is in threaded engagement with tube 25 to hold the bearing 2E in position. Another `bearing retaining ring 34 is employed on the casing 20.

The lower end of the tube 25 lits flush with the lower bearing 2l and in said lower end is a bushing 35 for guiding the drive shaft 36 arranged within the tube 25. The shaft 36 has longitudinal key grooves 3l on opposed walls thereof, adapted` to receive keys 38 for keying the shaft to` the tube 25 while permitting axial movement of the shaft 36 with respect to said tube. The keys 38 are held in position by a tapered sleeve39- slidably mounted on the tube 25, thus providing free coupling and un-coupling of the parts 25 and 36 whenever desired.

The lower end of the shaft 36 protrudes beyond the case .20 and has an enlarged socket portion 40, having a hexagon or other socket 4| for reception of the corresponding shank on the spindle of.l the attachment 2|, as is generally known in i this art. The enlargement 4|) rotates freelyfwith.-

in a bearaing 42 in an adaptor head 43 to which the attachment 2| is secured in any desiredmanner. The arm |3 which is actuated by the' rod l2 is coupled `with `the head 43, as clearly indicated in Fig. 2 of the drawing, so as to move said head with theattachment thereon downwardly and upwardly with respect to` a workpiece `supported on a table 44. The table 44 is adjustably clamped on the -column `|6 by a clamping lever 45 in order to position the workpiece at a predetermined distance with respect to the tapor other tool 2i' o the attachmentz A Also adjustable on the column |6is a tool guide plate 46, adjustment Vbeing made through-. a. clamping lever, as at4'l. As far as relative positions vof adjustment, the table 44 and plate 46 are honly diagrammatically illustrated in the accompanying drawing; Suitable adjustment will be `madeto suit` operating conditions.

Athe attachment 2| and its tool 2| is controlled by the depression of the foot pedal `Upon Vrelease of the pedal, the weight |4 will automatically return the attachment and associated parts to the raised position. i

With my improved machine, it will be apparent that the tube 25 with the pulleys a 24 thereon `maintain a 4fixed position with .respect'itoffthe 3 pulleys 22, thus providing a constantly alined drive between thefpulleys through the belt 23. The shaft 36 'is moved axially of the drive tube 25 in the operation of moving the tool toward.

and from the work. With this type of construction, the drive tuber 25 can be firmly supported.

and yet mounted for free rotation in the supports therefor and in operating the toolt'o"m'ove *the same toward and from the work-ia,comparativelyAv light mechanism is employed, which will require a minimum amount of counterbalance.

In order to take up 4fthe tortional strains to which the head 43 mayy beis'ubjected,.particularly When-'theadaptorfisntilized in conjunction with larger or `multiplewhead --tapping units, a head -43' isprovided, .tolwhichis attached guide .rods *5l -whichare-s1idab1y mounted inV upper and 'lower bearings 52 and 1 53 .of a. case 120'., substantiallylfsimilar tolthecasel. ilithfthis.construc- `tio'n, Ian-upper housing I8 is. modified .1to.a slight extent to accommodate the somewhat Awidercase construction, as clearlyappearing in. Fig...,3 of

. "thelfdrawing As the` other-'parts of theapparatus `sho'wnin Fig. Barethe same-'as thoseishown in Figs. u1 andr2, likereference have been utilized to designatelikeparts. Y l

`Itf'will, of course,be understood thatithe vhead -'43 includesl an adjustablestop screw, similar to `the screwvd. .The hood or housing I8, preferably includes.- a.l cover part 54 hinged, .aswseen at 55,

Ito-give access'. .to the rpulleys .24 in .shifting the belti23.. w

Having fully described my invention, what I fclaim.. as newland f desire :to secure by Letters "Patent is:

-...1...Inmachines ofthe. character described, .a ycasing having vertically spaced walls defining fupper and..lower.ends of the casing, bearings .in `said'upper and` lower walls, a ktubular drive .shaft rotatably mounted in .said hearings, .a driven "shaft fmovable 'axially of the tubular shaft, a

slidable lkeying means .between the. `.driven shaft .Sandlfsaid driveshaft, an adaptor .platefcarried by 4"said .driven-shaftbeyond said casing, the lower fend .portion of. .the driven shaft being. freely ro- :i-tata'ble.-insaid.y plate, means coupled with :said

:adaptor plate yfor moving `the vsameand .said

'.fdriven-shaft longitudinallyof the drive shaft, nan adjustable ,stop 'carried by. -and lmovable with Y .said plate and eng-aginglthe-casing.inlimiting movement of the adaptor plateiand shaft in 'pair of keysfin vsaid-drive shaftandloperating -in elongated slots :at .opposed 'sidesv of. thefdriven llshaft, ...and a single. sleeve slidable on said `drive shaft inretainingsaid keys .ingoperativesposition.

' `oneidirection, .said-,keying` meanswcomprising a 2. In machines of the character described, a'i

casing .having vertically spaced walls .defining .upperand .f lower endsflof .the casing, vbearings in said upper and lower walls, a tubularv .drive shaft .rotatably mounted in. said bearings, a f'dri-ven shaft movable axially fof/the tubular .z-shaft, a slidable keyingmeans between: the-.driven `,shaft and said drive .shaft,. an ladaptor .plate .car- Iriedbyv saiddriven shaft beyond Vsaidcasing, .the lower end .portion of theidriven shaft being. freely adaptor Aplate for moving, the lsame and said ...driven shaft longitudinally of .then drive .shaft,'.an adjustable stopcarried by and .movablewithsaid lplatefand engaging the casing in. limiting movefr otatablefinzsaid plateVmeans coupled with said ment of the adaptorplate` andvshaf-tinxone. di-

rection, said keying means comprising apair of keys in said drive shaft and operating in elonegated slotsga-t opposed sides o f the-.drivenshafta nfile -of this patent:

single sleeve slidable onl said drive shaft in re'- 'taining said lkeys inoperative position, and a pairof rods coupled with said adaptorplate and extending above said upper wall and having sliding bearings in said casing for taking up tor- ;tionalstrains to which said plate is subjected.

n 3. In tapping machines of the character described-employing an adaptor plate with which ,ak tapping attachment is adapted to be coupled for movement'toward and from a work-piece in the machine, a casing having spaced vertical Walls defining upper and lower ends of the casing, bearings vin l said walls, .a -tubular drivegshaft rotatable inY said bearings, means ,fixing fthe position of said drive shaft in the .casing `a .driven shaft keyedto and movable axiallymf Ythe drive shaft, said plate being mounted on .the

drivenshaft beyond said casing, vthe lower-.por-

`tion of said driven shaft projecting below and being movable towards and from the lower wall of the 'casing andbeing freely rotatable in said plate, meansfor `,retaining the plate against axial movement on said driven shaft, the keying ofthe driven shaft-to the drive shaft comprising apair of keys `in the drive shaft operating in elongated grcovesin Vthe driven shaft, a` sleeve slidable on the drive .shaft Vretaining the keys Yin operative position, and'meails COLlPled with said plate for moving said plate and'drivenshaft axially of the drive shaft in both directional. 4. In tapping machines of theiohararcter .de-

scribed `employingf an adapter plaie with which casingand .being freely rotatable in said plate,

means forretaining theplate againstl` axial movement on said driven shaft, the keying of the ,driven shaftV tothe drive-shaft comprising a pair of keys in the" drive shaft'operating in elongated .grooves in the driven'shaft-asleeve slidableon `the drive shaft .retaining the "keys in operative ,.position,. rneans coupledA with said plateffor, mov- King said, .plate .and drivenfshaft axially of the ydrive .shaft .in ,both directions, and .adjustable means carried by .theplate and engagingv the casing for limiting movement. thereof .and .the

,Y driven shaft in onedirection.

MELVIN H.

.REFERENCESCITED Y The-following-references areof record/in the Y UNITED STATES PATENTS .'Number Name Datev 688,653 Lambert Dec. 10, 1901 729,365 Lehm-an May.26, 1903 1,720,033 Caulkins July `9,1929 1,796,352 .Watson Mar. 17, .1931 l11,853,995 Klausmeyer May 17,1932 1 1,998,275 Emrick -Apr. 16, 1935 2,079,371 Emrick AMay 4, 1937 2,079,372 Emrick May 4,1937 .2,336,478 f Goldberg i,D ec. 14, .11943 

